minimum flow, or 15,800 horse-power at ordinary six ‘months flow. Above Tsu Lake, there is said to be a possibility of securing a head of 120 feet at Twin Gorge Falls which should yield 17,300 horse minimum flow, or 43,500 horse- months flow. Altogether, “power at ordinary power at ordinary six it is estimated the Taltson should have a capacity of at least 64,000 horse-power at ordinary minimum flow, or 160,000 horse-power a t ordinary six months flow. Power Markets ——No m arkets are in immediate prospect for power from the Talts on River, but lead-zine deposits which are known to exist to the south of Great Slave Lake and west of the Slave River might require a considerable supply of power if they should be developed in the future. Snowdrift River The Snowdrift River drains some 2,700 of rocky, lake-studded territory lying south of the easterly part of Great Slave Lake. It is reported to have a descent of 500 feet in its lower course below Siltaza Lake. No investigations of power possibilities have been made, but if it should be possible to develop the total head of 500 feet, the power capacity is tentatively estimated as 12,000 square miles horse-power at ordinary minimum flow, or 18,000 horse- » power at ordinary six months flow. yy Great Bear River Great Bear Lake, with an area of 11,440 square miles and a drainage area of 51,000 square miles, discharges into Great Bear River, which, after a westerly course of about 70 miles, flows into the Mackenzie River just below Fort Norman. About 35 miles from the mouth of the river, rapids are encountered which extend for about two and a half miles. These rapids, so called, are merely swift water flowing over a fairly wide and shallow river section strewn with numerous large boulders. Where the river cuts through the Franklin Mountains, at the foot of the rapids, it is about 650 feet in width; the right bank is rock and almost precipitous for a height of several hundred feet, and the left bank is a gradual clay slope rising to a height of 100 feet. Water Supply.—Great Bear Lake regulates the flow of Great Bear River and tends to maintain a fairly uniform flow throughout the year. No discharge records of the river have been obtained and its flow can only be estimated. Based on a run-off factor of 0-1 c.f.s. per square mile, the ordinary minimum flow would be 5,000 c.f.s., and a factor of 0-25 c.f.s. per square mile would give an ordinary six months flow of 12,500 c.f.s. Power Resources.—No power survey has been made of the Great Bear River, but an engineer of the Dominion Water and Power Bureau ascended the river in 1921 to the head of the rapids and observed the physical features. The total fall in the upper half of the river could probably be [ 82 ] concentrated by the construction of a dam at the point — where the river narrows to pass through the Franklin Mountains. The descent has not been measured, but a head of 25 feet would appear to be feasible. At this head 11,400 horse-power would be available at ordinary minimum flow, or 29,400 horse-power at ordinary six months flow. The possibilities for power development are not considered attractive. Power Markets.—The only market for power in the vicinity of the Great Bear River would appear to be at the oilfield now being operated at Norman Wells. It is not suggested, however, that the site mentioned in the foregoing would be a suitable source. Camsell River The Camsell River, draining an area of some 6,500 square miles of rocky, lake-studded territory, flows from the south into the southeastern part of Great Bear Lake. At White Eagle Falls, about 17 miles from the mouth, there is a natural fall of 54 feet, and investigations carried out by private interests in 1934-35 indicated that a head of some 70 feet could be concentrated at the site by the construction of a dam. Complete regulation of flow should be possible with storage in Clut, Grouard, and Hottah Lakes immedi- ately upstream from the power site. One complete year of flow records was obtained from December, 1933, to December, 1934. From these records and from records obtained in adjacent watersheds, natural run-off has been assumed at 0-10 ¢.f.s. per square mile for ordinary minimum flow, and 0-15 c.f.s. per square mile for ordinary six months flow. Estimates of power at White Eagle Falls, using these flow factors, are 4,100 horse-power and 6,200. horse-power, respectively. Power Markets.—The development of mineral deposits in the area to the southeast of Great Bear Lake offers the only known potential market for power on the Camsell River. Coppermine River The Coppermine River, which flows from the south into Coronation Gulf, drains some 29,000 square miles of rocky, barren territory plentifully interspersed with lake areas. Numerous rapids and falls occur along the river course, but information is lacking with respect to actual descents except at Bloody Falls, near the mouth, where there is-a fall of 12 feet ina shelving cascade about 300 yards long. Both banks consist of high walls of red sandstone, and it has been suggested that a head of 80 feet could be secured by the construction of a dam at Bloody Falls. The only information regarding flow is from three measurements made at low winter flow in 1932, 1935, and 1936 for the Dominion Water and Power Bureau by the Royal Canadian Mounted Police. Based on these measurements, an ordinary minimum flow of 1,700 c.f.s. has been assumed with 2,550 c.f.s. being ordinarily available for six months of the year.